function CommonTest (testType, observation) {
	// body...
	this.testType = testType;
	this.observation = observation;
}

var arrayCommonTest = {
	Cr: new Test("Cr", 0),
	Ni: new Test("Ni", 0),
	pH: new Test("pH", 0),
	Bl: new Test("Bl", 0),
	SG: new Test("SG", 0)
};